1. Toss the cauliflower and mushrooms in the oil, salt and pepper, place on a baking sheet in a single layer and roast in a preheated 400F oven until they start to caramelize, about 20-30 minutes, mixing half way through.2. Start cooking the pasta as directed on the package. Cook the pancetta in a pan, pour off all but a tablespoon of the grease from the pan, add the garlic, cook for 30 second and turn off the heat.3. Mix the egg, cheese, pepper and salt and parsley in a bowl. Drain the cooked pasta reserving some of the water.4. Mix the pasta, egg mixture, cauliflower and mushrooms into the pan with the pancetta, adding reserved pasta water as needed.Note: To speed things up, about 20 minutes into roasting the cauliflower and mushrooms, get your pot of water for the pasta on the stove and start bringing it to a boil.Option: Replace the parmigiano reggiano with pecorino romano.Source: Closet Cooking